This invention relates to a chuck for a rotary rock drilling machine and in particular for a diamond drilling machine.
Some rotary diamond drilling machines are thrusted by means of a feed screw. The feed screw carries a chuck which locks on to the drill rods. Conventionally such chucks are opened and closed by means of manually turned dog screws. Thus much time is wasted when a new drill rod has to be fitted at the end of the stroke of the feed screw.
It is an object of the invention to provide a chuck which does not rely on dog screws and which operates more or less automatically at least in the preferred embodiments.